What two things are needed to create an emission nebulae?
A) interstellar gas and dust
B) hydrogen fusion and helium ionization
C) cool stars and much interstellar dust
D) hot stars and interstellar gas, particularly hydrogen
E) hydrogen gas and carbon dust
D
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A bimetallic strip is made out of two strips of metal bonded together. Each strip is 20.0 cm long and 1.00 mm thick
One strip has a coefficient of thermal expansion 4.00 × 10-6/K and the other has a coefficient of thermal expansion 3.00 × 10-6/K. At 20.0°C the strip is straight. What is the inner radius of curvature of the composite strip at 200°C? A) 15.2 cm B) 2.22 m C) 1.27 m D) 34.8 cm E) 5.56 m
Relativity dealing with gravitation is known as:
a. gravitational relativity. c. general relativity. b. Galilean relativity. d. inertial relativity.
As a projectile moves its speed stays constant while its direction changes
Indicate whether the statement is true or false
Objects A and B, of mass M and 2M respectively, are each pushed a distance d straight up an inclined plane by a force F parallel to the plane. The coefficient of kinetic friction between each mass and the plane has the same value mk. At the highest point,
a. KA = Fd = KB. b. KA = (F - mkMg cosq)d; KB = (F - 2mkMg cosq)d. c. KA = (F - Mg sinq)d; KB = (F - 2Mg sinq)d. d. KA = (F - Mg sinq - mkMg cosq)d; KB = (F - Mg sinq - mkMg cosq)d. e. KA = (F - Mg sinq - mkMg cosq)d; KB = (F - 2Mg sinq - 2mkMg cosq)d.